Biomes 3
18.2 The distribution of biomes is determined by climate
General Classification Scheme
-Tundra
-Taiga/Boreal Forest
-Mountainous Coniferous
-Deciduous Forest
-Savanna
-Shrublands
-Grasslands
-Desert
-Subtropical & Tropical
Grassland
Grasslands are lands dominated by grass. Ha ha. Well its true. But
WHY? Edaphic in some cases. Sometimes temperature. But in
midwestern US- mostly disturbance driven structure. Today almost all of
the grasslands of the US have been turned into soybean fields or corn.
Big bluestem (Andropogon gerardii)
Characteristic species of tall grass
prairie. Incredibly deep root system.
18.20 Tallgrass prairie in Nebraska, in the center of the U.S.
American bison: Bison bison
Keystone species, and the center of a
flourishing an vibrant human culture
(Ogllala Sioux) they were nearly
“hunted” to extinction by Anglos. It
wasn’t hunting, actually, it was slaughter:
Ecological Ignorance meets Basic
Human Avarice…
Ogallala Aquifer
Long term sustainability of Great Plains
agriculture is very much in doubt…
Water is in short supply, water table is
dropping, the largest aquifer in the US,
by far, is being depleted.
Thousands of ghost towns, exceedingly
low population density…
http://en.wikipedia.org/wiki/Buffalo_Commons
18.26 Alpine grassland in Rocky Mountain National Park, Colorado
-Steppe
…I am not going into detail on Steppe. It is high elevation grasslands in
Siberia, etc.
http://www.youtube.com/watch?v=Re644qgnCtw
18.2 The distribution of biomes is determined by climate
General Classification Scheme
-Tundra
-Taiga/Boreal Forest
-Mountainous Coniferous
-Deciduous Forest
-Savanna
-Shrublands
-Grasslands
-Desert
-Subtropical & Tropical
-Desert
Focus on the desert southwest
Columnar Cacti/sub-tree, shrubs
Sub shrubs/Opuntia
Perennial grass
Dune
Death valley
Sonoran desert
very species rich…
Saguaro (Carnegiea gigantea)
10 feet tall
Is found in the Sonoran desert.
Arches, Utah
Saguaro (Carnegiea gigantea)
10 feet tall
Is found in the Sonoran desert.
Side winder rattlesnake: (Crotalus cerastes)
http://www.youtube.com/watch?v=725R5RvtiUI
Road Runner: Geococcyx californianus
http://en.wikipedia.org/wiki/Geococcyx
http://www.youtube.com/watch?v=
BxYUS_shPfo&NR=1
18.2 The distribution of biomes is determined by climate
General Classification Scheme
-Tundra
-Taiga/Boreal Forest
-Mountainous Coniferous
-Deciduous Forest
-Savanna
-Chaparral
-Grasslands
-Desert
-Subtropical & Tropical
-Subtropical &
tropical forest
18.5 (A) Interior of Rara Avis Rainforest in Costa Rica, (B) Epiphytes are symbiotic commensals
18.6 A tropical montane forest in the La Paz Waterfall Gardens Nature Park, Costa Rica
Rainforests:
6% of Earth’s surface- 50% of the species
In the Amazon- 170,000 species of plant
(68% of the known total- 250,000)
- In 5 acres- 300 species of tree.
- 30% of all bird species
Insect diversity is
unimaginable, and unknown:
One example:
2.5 acres- 18,000 species of
beetle- most of them were new
to science (had no name).
Global Rainforest Loss
35% lost
50% lost
52% lost
Biomes 3